Blog
Mert Özen's blog posts on software development, backend, frontend, and DevOps.
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.NET Core Web API
36
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JavaScript Basics
19
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16
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12
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28
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29
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21
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Advanced C#
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C# Versions
6
2 posts found
#narrowing
Frontend
PART 09
TypeScript Type Guards: Type Predicates and Assertion Functions
We write type predicates with x is T and assertion functions with asserts, and look at TypeScript 5.5's inferred type predicates and narrowing arrays with filter, pitfalls included.
3 Nov 2026
8 min
28
Frontend
PART 09
Narrowing in TypeScript: Shrinking Unions with Control Flow Analysis
We see how TypeScript narrows unions through control flow analysis: typeof, truthiness, equality, in and instanceof checks, discriminated unions and exhaustive checks with never.
3 Nov 2026
8 min
26